Question: $ { \left[\begin{array}{rr}{4} & {-2} \\ {-1} & {-1}\end{array}\right]-\left[\begin{array}{rr}{-2} & {2} \\ {1} & {0}\end{array}\right] = {?} } $
To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rr}{4}-{-2} & {-2}-{2} \\ {-1}-{1} & {-1}-{0}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{6} & {-4} \\ {-2} & {-1}\end{array}\right]}$